In any listening environment, knowing the precise distance from a sound generator, such as a loudspeaker, to a listening position, as well as the precise distance between sound generators, and from each sound generator to a boundary wall behind it, is required for setting up the sound generators in such a way as to ensure optimal sound quality. However, software means for measuring the distance between an apparatus such as a smartphone or tablet device and a sound generator can currently only be accomplished through the use of software that does internal calculations based upon either visual surveying or a sonar signal, and both of those techniques are inaccurate and lack the precision required.
Past software systems were capable of only calculating the rough measurement of distance from a smartphone or tablet device to a sound generator, such as a loudspeaker, within a tolerance of several inches to several feet, which is insufficient accuracy when determining proper alignment of audio setups in home, studio or live performance environments. This software provides a significant improvement over past systems, with measurable accuracy within a fraction of an inch, making it suitable for calibrating audio setups with fine precision.
Time of Arrival (ToA or TOA), also known as Time of Flight (ToF) is another measurement technique which measures the travel time of a radio signal from a single transmitter to a single receiver. See for example http://en.wikipedia.org/wiki/Time of arrival and http://www.symeo.com/English/Technology/, both of which are incorporated herein by reference in their entirety. ToA or ToF is different from the present invention because that technology, for example, relies on radio waves whereas the present invention, as described more fully below, relies on audible impulse signals.
This invention provides a significant improvement over past systems for measuring distance with, for example, a smartphone or tablet device, with measurable accuracy within a fraction of an inch, making it suitable for even the most demanding professional applications.